External Breast Prosthesis and Method of Fabricating Same

ABSTRACT

An external breast prosthesis having a thin-walled outer shell and an air-filled interior cavity. The prosthesis is fabricated using a method and die set to form the two-part shell without internal supporting structure. The method provides a repeatable process which yields a prosthesis having durable air-tight seal between the anterior and posterior shell and a Class-A exterior surface which accurately replicates the visual and tactile characteristics of a human breast.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/255,910, filed on Oct. 29, 2009. The entire disclosure of the aboveapplication is incorporated herein by reference.

FIELD

The present disclosure relates to a breast prosthesis and method offabricating same, and in particular to an external air-filled breastprosthesis having a human-like appearance.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

The use of prosthesis is well known for the purpose of replicating oraugmenting anatomical features of the human body, and in particular thehuman breast. To be acceptable, a breast prosthesis must accuratelyreplicate the size and shape of the anatomy, as well as the function ofsuch anatomy. In addition, the prosthesis must be ergonomicallycompatible and comfortable for the wearer.

The art is replete with various internal and external breast prostheses.In some instances, a relatively thin outer elastic shell is formed froman elastic silicone material. In these embodiments, the prosthesis iseither made of solid silicon or the interior cavity of the prosthesis isfilled with a material which provides internal support. Such fillermaterials may include various foams or other biocompatible fluids suchas saline, silicone gel or natural triglyceride oils. These prostheseshave a tendency to be heavy and/or inaccurate at replicating the formand function of the subject anatomy.

Accordingly, there is a need the art to provide an external breastprosthesis with a thin outer shell formed of an elastomeric material andan interior air-filled cavity, as well as a method and die set forfabricating such an external breast prosthesis.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

As further set forth in detail below, this disclosure provides anexternal breast prosthesis having a thin-walled outer shell and anair-filled internal cavity. The prosthesis is fabricated using a processand die set which provides a two part shell including an anteriorcup-shaped portion and a posterior backer which when assembled definesan air-tight cavity. The nipple structure of the prosthesis is formedwith a rayon flocking material having a fleshy color consisting ofvarious tints of red, purple and gold. The outer shell is formed of anelastomeric material, preferably an elastic silicone material which hasbeen vacuum treated to remove air that would otherwise cause bubbles,pits or voids in the thin-walled prosthesis. This disclosure furtherprovides a method and die set for fabricating the thin-walled air-filledprosthesis.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 illustrates a first mold assembly in which the anteriorcup-shaped portion of the prosthesis is formed;

FIG. 2A illustrates a second molding assembly in a pre-assembled statewith a thickened layer of elastic silicone material spread on the dieplate;

FIG. 2B illustrates the second molding assembly shown in FIG. 2A withthe die cavity placed on top of the die plate;

FIG. 3 is an illustration of the breast prosthesis in its finalizedform; and

FIG. 4 is a flow chart setting forth the processing steps used in thefabrication of the breast prosthesis.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

With reference now to the figures, an external breast prosthesis 10having a thin-walled elastomeric shell 12, 16 with an air-filledinterior cavity 18 is illustrated. In addition, the method and die setfor fabricating this prosthesis is illustrated and described. Withparticular reference to FIGS. 1-3, the external breast prosthesis 10includes a thin-walled anterior shell 12 having a perimeter edge portion14 joined to a thin-walled posterior shell 16. In this configuration theanterior shell 12 and posterior shell 16 are arranged to define anair-filled interior cavity 18. The anterior shell 12 has a nipple/areolaregion 20 formed therein. As best seen in FIG. 3, the perimeter edge 14of the anterior shell 12 is a chamfered perimeter edge 14 formed thereonwhich complements the edge defined by the posterior shell 16. Inparticular, the perimeter edge 14 bisects the interface between anteriorshell 12 and posterior shell 16 to form a mitered joint. As noted above,the prosthesis is fabricated with an elastomeric material, preferably anelastic silicone material.

The breast prosthesis 10 is fabricated by injection molding the anteriorshell 12 and then position forming the posterior shell 16 onto theanterior shell. The die sets 30, 50 used in this fabrication processsufficiently support the anterior shell 12 such that the prosthesis canbe fabricated with an air-filled cavity and without internal support. Inparticular, a first mold assembly 30 as shown in FIG. 1 includes a lowerdie 32 and an upper cover 34. A series of pins 36 extend across the dieseparation surface and align the upper cover 34 with the lower die 32.The lower die 32 has a generally concave die cavity 38 formed therein.The bottom region 40 of the die cavity 38 is shaped to replicate thenipple/areola region of a human breast.

As presently preferred, the die cavity 38 is formed using a machiningprocess which yields a Class-A exterior surface for the anterior shell12 of the breast prosthesis 10. In particular, the interior die cavity38 is machined to a precision surface based upon 3-dimensional modelingdata similar to the techniques utilized in fabrication of automotivebody panels. The upper die cover 34 has a generally convex surface 42which complements the concave surface 38 formed on lower die 32. Theconvex surface 42 terminates at an angled annular surface 44 whichdefines the chamfered perimeter edge 14 on anterior shell 12. A gate 46is formed through upper die cover 34 and extends into the cavity formedbetween concave surface 38 and convex surface 42. The gate 46 is coupledto an injection molding system 48 suitable for injecting an elastomericmaterial into the cavity.

A second die assembly 50 is provided which includes the lower die cavity32 used in the first die assembly 30 and a die plate 52. The die plate52 has a generally flat upper die surface 54 which may abut theperimeter edge 14 of the anterior shell 12 and extends inwardly towardsthe nipple/aerola region 20. As shown in FIG. 2B, the die cavity 32 ispositionable into an abutting relationship with die plate 52 on a margin56 which may be slightly relieved from the upper die surface 54. Gates58 are formed in the margin 56 of the die plate 52 and extend from thehorizontal surface to the boundary 60 of the die plate 52 for directingexcess elastomeric material away from the prosthesis 10 duringfabrication.

With reference now to FIG. 4, the fabrication process will be furtherexplained. As presently preferred, a first mold cavity 32 is provided inan upright position with the concaved cavity facing upwardly. Thenipple/areola region 20 of the breast prosthesis 10 is formed bydepositing elastomeric material colored with pigments of red, purple andgold and mixed with rayon flocking fibers to simulate the color andtexture of the nipple/areola region of a human breast. This material ispermitted to partially cure.

While the nipple/aerola region cures, the first mold cavity 32 isenclosed with a die cover 34 yielding a thin-walled cavity to definewhat will become the anterior shell 12. Conventional injection moldingprocess is used to inject elastomeric material into the first moldassembly 30 and form the anterior shell 12. The anterior shell 12 isallowed to substantially cure, typically for approximately four hours.

Once the anterior shell 12 is cured, the die cover 34 is removed fromthe die cavity 32 and the sprue 48 extending from the interior surfaceof anterior shell 12 is trimmed. A die plate 52 is provided with theupper surface 54 which is spread with a partially cured elastomericmaterial. In this regard, it is important that the elastomeric materialbe partially cured to a degree sufficient such that its viscosity willallow the elastomeric material to remain on the relatively flathorizontal surface 54 formed on die plate 52. Alternatively, the dieplate 52 may be provided with a seal or similar feature around theboundary 60 for confining the elastomeric material on the upper surface54.

A layer of adhesive 62 is applied to the perimeter edge 14 of theanterior shell 12. A suitable adhesive is selected to enhance adhesionand induce vulcanization or similar process in which the polymermolecules are linked to other polymer molecules by atomic bridges toform an air tight bond. While a vulcanization process in presentlypreferred, other acceptable processes such as similar thermostatic orthermoplastic processes may be utilized to achieve an air tightinterface.

Next, the die cavity 32 is rotated 180° from its position as shown inFIG. 1 into an inverted position as shown in FIGS. 2A and 2B. The diecavity 32 is then lowered on top of die plate 52 and aligned with pins36 in a manner similar to that described with reference to FIG. 1.Sufficient adhesion exists between the anterior shell 12 and die cavity32 to support the anterior shell 12 in the concave position aboveposterior portion 16. The interior cavity 18 defined by anterior shell12 and posterior portion 16 captures ambient air to create air-filledinterior cavity 18. The breast prosthesis 10 is allowed to fully cure,taking approximately three to six hours.

Once fully cured, the die plate 52 is removed form the die cavity 32.The breast prosthesis 10 is removed from die cavity 32. The moldedbreast 10 may include some flash material extending from the perimeterregions which may be trimmed using conventional processes. The breastprosthesis 10 is then washed and talced to provide an acceptable tactilecharacteristic simulating that of the human skin.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention. Individual elements or features ofa particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the invention, and all such modificationsare intended to be included within the scope of the invention.

1. An external breast prosthesis comprising: a thin-walled posterior shell; a thin-walled anterior shell defining a cup shaped body having a chamfered perimeter edge, the posterior shell covering the cup-shaped body to form an air-filled interior cavity; wherein the chamfered perimeter edge forms a mitered joint between the anterior shell and the posterior shell.
 2. The external breast prosthesis of claim 1 wherein the anterior shell and the posterior shell are formed with an elastomeric material.
 3. The external breast prosthesis of claim 2 comprising further comprising an adhesive layer interposed between the chamfered perimeter edge and the posterior shell.
 4. The external breast prosthesis of claim 1 comprising further comprising an areola region formed on a surface of the anterior shell opposite the posterior shell.
 5. The external breast prosthesis of claim 4 wherein the areola region has a nipple formed therein.
 6. The external breast prosthesis of claim 4 wherein the anterior shell, the areola region and the posterior shell are formed with an elastomeric material, the areola region further including a flocking fiber.
 7. A method for molding an external breast prosthesis comprising: providing a die mold having a concaved cavity; positioning a die cover on the first mold to enclose the concaved cavity to form a thin cup-shaped die cavity; injecting an elastomeric material into the die cavity; curing the elastomeric material in the die cavity to form a thin-walled anterior shell; removing the die cover from the die mold; forming a chamfered perimeter edge on the anterior shell; spreading an elastomeric material on a surface of a die plate to form a thin-walled posterior shell; locating the die mold in an inverted position on top of the die plate; curing the elastomeric material on the die plate such that the anterior shell bonds with the posterior shell at the chamfered perimeter edge to form an external breast prosthesis having an air-filled interior cavity, wherein the chamfered perimeter edge forms a mitered joint between the anterior shell and the posterior shell; removing the die mold from the die plate: and removing the breast prosthesis from the mold cavity.
 8. The method for molding an external breast prosthesis of claim 7 further comprising vacuum treating the elastomeric material used to form the anterior shell prior to injecting the elastomeric material into the die cavity.
 9. The method for molding an external breast prosthesis of claim 7 wherein the elastomeric material spread on the surface of the die plate is partially cured to a degree sufficient so the viscosity of the elastomeric material allows the elastomeric material to remain on the surface of the die plate.
 10. The method for molding an external breast prosthesis of claim 7 further comprising: depositing a colored elastomeric material in a local region of the concaved cavity to form an areola region; and allowing the elastomeric material in the local region to at least partially cure prior to injecting the elastomeric material into the die.
 11. The method for molding an external breast prosthesis of claim 10 further comprising mixing a flocking fiber with the colored elastomeric material used to form the areola region.
 12. The method for molding an external breast prosthesis of claim 7 further comprising applying an adhesive layer on the chamfered perimeter edge of the anterior shell prior to locating the die mold on top of the die place.
 13. The method for molding an external breast prosthesis of claim 7 wherein a sprue extends from an interior surface of the anterior shell after the die cover is removed from the die mold, the method further comprising trimming the sprue near the interior surface of the anterior shell.
 14. A die set for molding an external breast prosthesis comprising: a die mold having a concaved cavity formed in a mold die face; a die cover having a convex die face complementing the concaved cavity terminating at an annular angled face, wherein the die mold and the die cover define a first mold assembly having a cup-shaped die cavity with a chamfered perimeter edge when the die cover is placed on top of the die mold; a die plate having a generally flat upper die surface, wherein the die mold and the die plate define a second mold assembly configured to fabricate a thin-walled external breast prosthesis having an anterior shell and a posterior shell forming an air-filed interior cavity without an internal support.
 15. The die set for molding an external breast prosthesis of claim 14 wherein the concaved cavity of the die mold is machined with a precision surface which yields a Class-A exterior surface for the anterior shell formed therein.
 16. The die set for molding an external breast prosthesis of claim 14 wherein the die cover comprises a gate extending therethrough and terminating at the convex die face, the gate being operably coupled to an injection molding system for injecting an elastomeric material into the cup-shaped die cavity.
 17. The die set for molding an external breast prosthesis of claim 14 wherein the first mold assembly further comprises a set of pins extending across the mold die face between the die mold and the die cover to align the first mold assembly.
 18. The die set for molding an external breast prosthesis of claim 14 wherein the die plate of the second mold assembly comprises a central raised portion extending upwardly into the concaved cavity of the die mold and a generally flat margin extending from the central raised portion to a boundary of the die plate.
 19. The die set for molding an external breast prosthesis of claim 18 wherein the die plate comprises at least one gate formed in the margin of the die plate and extending to the boundary thereof.
 20. The die set for molding an external breast prosthesis of claim 14 wherein the second mold assembly further comprises a set of pins extending across a die separation surface between the die mold and the die plate to align the second mold assembly. 